The present invention relates to an apparatus for controlled sorting by way of deflection of sheet-like objects such as veneer sheets in a desired manner in a continuous train of sheets from one transport conveyor of said sheets to another conveyor. The need for this kind of apparatus occurs, e.g., in the manufacture of plywood when veneer of different grade must be sorted into respective stacks or to a separate post-processing step.
Deflection of a veneer sheet is conventionally based on information obtained from the sheet by means of a suitable monitoring system located on the travel path of the sheets. Next on the sheet travel path, there are located apparatuses that on the basis of this information can deflect the sheet from one path to another. The deflecting apparatuses are adapted to cooperate with the conveyor types used and are based on different kinds of picking, lifting and pressing means that momentarily can be actuated into their working positions. These deflecting means have in common that they are, when actuated, stationary in respect of the travel of the moving sheets. Obviously, this causes a stop in the travel of the sheet to be deflected. As known in the art, attempts have been made to minimize the disadvantages of the stopping deflection step by virtue of arranging the deflection step to occur at a maximized speed.
In the apparatus according to the invention, the stopping effect imposed on the sheet to be deflected by the deflecting means or apparatus is entirely eliminated during the sorting of veneer sheets in a desired manner onto different travel paths. The apparatus includes a sheet-moving transport conveyor comprising parallel-travelling, spaced-apart moving transport conveyor elements such as belts, and a deflecting conveyor travelling locally at least over a certain distance substantially in the same direction with the first conveyor. The transport conveyor has thereto adapted lifting means that in a controlled manner can reach above the transport level of the transport conveyor via the gaps arranged between said conveyor elements, said lifting means being arranged to be elevated into an abutting position against the deflecting conveyor and simultaneously coinciding with the movement of the latter conveyor.